Torsional damper device

Abstract

A torsional damper device, for use in friction disks in automobile vehicle clutches, for example, comprises at least two coaxial parts rotatable relative to one another within defined limits and damper means adapted to oppose such relative rotation. The damper means comprise at least one friction ring, two annular members and an elastic prestressing member disposed axially between the annular members. The prestressing member is adapted to urge the friction ring axially against one of the coaxial parts. It and one of the annular members constitute a pair of members of which one has at least one primary transverse land which is circumferentially subdivided and of which the other has at least two secondary transverse lands which are axially offset and circumferentially subdivided and each of which is adapted to contact selectively the primary transverse land.

We claim: 
     
       1. A torsional damper device comprising at least two coaxial parts disposed to rotate relative to each other within defined limits and damper means for opposing such relative rotation of said coaxial parts, each of said coaxial parts including a coaxial member, a friction assembly for producing frictional torque in the course of relative rotation of said coaxial parts, said friction assembly comprising a plurality of annular members including said coaxial members of said coaxial parts, an elastic prestressing member and a friction ring member, said elastic prestressing member and said friction ring member being disposed axially between said coaxial members, said friction ring member being coupled for rotation with one of said coaxial members over at least part of said defined limits of relative rotation, said elastic prestressing member applying an axial bias to said friction ring member, said elastic prestressing member and another adjacent one of said annular members of said friction assembly having cooperable means for selectively preloading said friction assembly, a plurality of circumferentially spaced primary lands on one of said elastic prestressing member and said another adjacent annular member of said friction assembly, and two relatively axially offset pluralities of circumferentially spaced secondary lands on the other of said elastic prestressing member and said another adjacent annular member of said friction assembly, said plurality of primary lands being cooperable with one of said pluralities of secondary lands for setting the preload of said friction assembly, and said elastic prestressing member and said another adjacent annular member being rotatable with the same coaxial member during relative rotation of said coaxial parts. 
     
     
       2. A device according to claim 1, wherein said plurality of primary lands are disposed on said elastic prestressing member. 
     
     
       3. A device according to claim 2, wherein said pluralities of secondary lands are disposed on said friction ring. 
     
     
       4. A device according to claim 3, wherein said elastic prestressing member is disposed axially between said friction ring member and said one coaxial member. 
     
     
       5. A device according to claim 3, wherein said friction ring member has steps of different heights defining said pluralities of secondary lands and said elastic prestressing member comprises a corrugated spring washer including a plurality of circumferentially spaced corrugations defining said plurality of primary lands. 
     
     
       6. A device according to claim 3, wherein said friction ring member bears directly against the other of said coaxial members. 
     
     
       7. A device according to claim 3, wherein said friction assembly includes a further annular member defining a clamping ring member disposed between said elastic prestressing member and said friction ring member, and wherein pluralities of secondary lands are disposed on said clamping ring. 
     
     
       8. A device according to claim 7, wherein said clamping ring member has notches of different axial depths defining the pluralities of secondary lands and said elastic prestressing member comprises a plurality of radial fingers fixed to the other of said coaxial members and selectively cooperable with notches of different axial depths defining said pluralities of secondary lands. 
     
     
       9. A device according to claim 8, wherein said clamping ring member is fixed for rotation with the other of said coaxial members. 
     
     
       10. A device according to claim 9, wherein said friction ring member is fixed to a support flange coupled for rotation with circumferential play with said one coaxial member. 
     
     
       11. A device according to claim 10, wherein said support flange comprises axially bent lugs and said one coaxial member has openings, said lugs being received with circumferential play in said openings. 
     
     
       12. A device according to claim 11, wherein said coaxial members of said coaxial parts respectively comprise two guide rings rotationally fixed together and a flange disposed axially between said guide rings, said damper means comprising circumferentially acting elastic members engaged in openings in said guide rings and said flange, said support flange comprising at least two radial yokes surrounding with play at least two of said elastic members, said bent lugs being disposed between branches of the same yoke and engaged with play in said openings in said flange associated with said elastic members. 
     
     
       13. A device according to claim 1, wherein said pluralities of secondary lands are disposed on said elastic prestressing member. 
     
     
       14. A device according to claim 13, wherein said another adjacent annular member features circumferentially spaced openings adapted to receive at least one of said pluralities of secondary lands and defines said plurality of primary lands. 
     
     
       15. A device according to claim 14, wherein said elastic prestressing member is a corrugated spring washer having corrugations of different axial heights defining the respective pluralities of secondary lands. 
     
     
       16. A device according to claim 14, wherein said elastic prestressing member is generally frustoconical and has axially projecting lugs of different lengths. 
     
     
       17. A device according to claim 14, wherein said coaxial members of said coaxial parts respectively comprise two guide rings rotationally fixed together and a flange disposed axially between said guide rings, said plurality of primary lands being disposed on one of said guide rings. 
     
     
       18. A device according to claim 1, wherein said elastic prestressing member comprises a corrugated spring washer featuring radial lugs for angularly positioning said corrugated spring washer through said coaxial member of one of said coaxial parts. 
     
     
       19. A device according to claim 1, wherein said elastic prestressing member comprises a spring washer having a radial tab for adjusting the angular position of said plurality of primary lands relative to said pluralities of secondary lands, access being provided through one of said coaxial members to said radial tab. 
     
     
       20. A torsional damper device comprising at least two coaxial parts disposed to rotate relative to one another within defined limits and damper means for opposing such relative rotation of said coaxial parts, said damper means including at least one friction ring, two annular members and an elastic prestressing member disposed axially between said annular members and urging said friction ring axially against one of said coaxial parts, said one annular member having at least one primary transverse land which is circumferentially subdivided and said elastic prestressing member having at least two secondary transverse lands which are axially offset relative to each other and circumferentially subdivided, each of said secondary transverse lands being positioned to contact selectively said primary transverse land, and said one annular member having circumferentially distributed openings for having at least one of said secondary transverse lands pass axially therethrough. 
     
     
       21. A torsional damper device comprising at least two coaxial parts disposed to rotate relative to one another within defined limits and damper means for opposing such relative rotation of said coaxial parts, said damper means including at least one friction ring, two annular members and an elastic prestressing member disposed axially between said annular members and urging said friction ring axially against one of said coaxial parts, said one annular member having at least one primary transverse land which is circumferentially subdivided and said elastic prestressing member having at least two secondary transverse lands which are axially offset relative to each other and circumferentially subdivided, each of said secondary transverse lands being positioned to contact selectively said one primary transverse land, and said elastic prestressing member being generally frustoconical and having axially projecting lugs. 
     
     
       22. A device according to claim 20, wherein said elastic prestressing member is generally frustoconical and has axially projecting lugs. 
     
     
       23. A device according to claim 20, wherein one of the coaxial parts comprises two guide rings fixed for rotation together, and the other of the coaxial parts comprises a flange disposed between the guide rings, the primary land being disposed on one of said guide rings.